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57 - Lanthanum lanthanide

Discovered by Carl Gustaf Mosander in 1839

Lanthanum

Lanthanum is a soft, ductile, silvery-white metallic chemical element with symbol La and atomic number 57. It tarnishes rapidly when exposed to air and is soft enough to be cut with a knife. It gave its name to the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table:it is also sometimes considered the first element of the 6th-period transition metals.
Shell Electrons Orbitals
1 2 2 in 1s
2 8 2 in 2s + 6 in 2p
3 18 2 in 3s + 6 in 3p + 10 in 3d
4 18 2 in 4s + 6 in 4p + 10 in 4d
5 9 2 in 5s + 6 in 5p + 1 in 5d
6 2 2 in 6s
LanthanumLa Electron 1 Electron 2 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 1 Electron 2
138.91  u Atomic Mass
2.7  Å Atomic Radius
3737  K Boiling Point
2.07  Å Covalent Radius
6.16  g/cm³ Density
53 Electron Affinity
1.1 Electronegativity
5.58  eV First Ionization Energy
1193.15  K Melting Point
6 Number of Shells
57 Atomic Number
2, 8, 18, 18, 9, 2 Electron Shell Occupations